build.zig

const std = @import("std");

// Although this function looks imperative, note that its job is to
// declaratively construct a build graph that will be executed by an external
// runner.
pub fn build(b: *std.Build) void {
    // Standard target options allows the person running `zig build` to choose
    // what target to build for. Here we do not override the defaults, which
    // means any target is allowed, and the default is native. Other options
    // for restricting supported target set are available.
    const target = b.standardTargetOptions(.{});

    // Standard optimization options allow the person running `zig build` to select
    // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall. Here we do not
    // set a preferred release mode, allowing the user to decide how to optimize.
    const optimize = b.standardOptimizeOption(.{});

    const lib = b.addStaticLibrary(.{
        .name = "zig-ebpf",
        // In this case the main source file is merely a path, however, in more
        // complicated build scripts, this could be a generated file.
        .root_source_file = b.path("src/root.zig"),
        .target = target,
        .optimize = optimize,
    });

    // This declares intent for the library to be installed into the standard
    // location when the user invokes the "install" step (the default step when
    // running `zig build`).
    b.installArtifact(lib);

    const exe = b.addExecutable(.{
        .name = "zig-ebpf",
        .root_source_file = b.path("src/main.zig"),
        .target = target,
        .optimize = optimize,
    });

    // This declares intent for the executable to be installed into the
    // standard location when the user invokes the "install" step (the default
    // step when running `zig build`).
    b.installArtifact(exe);

    // This *creates* a Run step in the build graph, to be executed when another
    // step is evaluated that depends on it. The next line below will establish
    // such a dependency.
    const run_cmd = b.addRunArtifact(exe);

    // By making the run step depend on the install step, it will be run from the
    // installation directory rather than directly from within the cache directory.
    // This is not necessary, however, if the application depends on other installed
    // files, this ensures they will be present and in the expected location.
    run_cmd.step.dependOn(b.getInstallStep());

    // This allows the user to pass arguments to the application in the build
    // command itself, like this: `zig build run -- arg1 arg2 etc`
    if (b.args) |args| {
        run_cmd.addArgs(args);
    }

    // This creates a build step. It will be visible in the `zig build --help` menu,
    // and can be selected like this: `zig build run`
    // This will evaluate the `run` step rather than the default, which is "install".
    const run_step = b.step("run", "Run the app");
    run_step.dependOn(&run_cmd.step);

    // b.addModule("zig-ebpf", .{});
    // Creates a step for unit testing. This only builds the test executable
    // but does not run it
    // .
    const zig_ebpf = b.addModule("zig-ebpf", .{ .root_source_file = b.path("src/root.zig") });

    exe.root_module.addImport("zig-ebpf", zig_ebpf);
    lib.root_module.addImport("zig-ebpf", zig_ebpf);

    const test_step = b.step("test", "Run unit tests");

    // var test_files = std.ArrayList([]const u8).init(b.allocator);
    // defer test_files.deinit();
    // var options = b.addOptions();

    // Add all files names in the src folder to `files`
    const dir = std.fs.cwd().openDir("tests", .{ .iterate = true });
    // var dir_u = dir catch |e| {
    //     std.log.warn("error: {}", .{e})
    //
    // };
    if (dir) |dir_value| {
        var it = dir_value.iterate();
        while (it.next()) |file| {
            // std.log.warn("err {any}", .{file});
            // TODO: add extenson check
            if (file == null) {
                break;
            }
            if (file.?.kind != std.fs.File.Kind.file) {
                continue;
            }
            var filename: []u8 = &[_]u8{};
            var temp = concatAndReturnBuffer(b.allocator, "tests/", file.?.name) catch unreachable;
            if (temp.toOwnedSlice()) |name_slice| {
                filename = name_slice;
            } else |_| {}
            const lib_unit_tests = b.addTest(.{
                .root_source_file = b.path(filename),
                .target = target,
                .optimize = optimize,
            });
            lib_unit_tests.root_module.addImport("zig-ebpf", zig_ebpf);

            const run_lib_unit_tests = b.addRunArtifact(lib_unit_tests);

            // Similar to creating the run step earlier, this exposes a `test` step to
            // the `zig build --help` menu, providing a way for the user to request
            // running the unit tests.
            test_step.dependOn(&run_lib_unit_tests.step);
            // try files.append(b.dupe(file.name));
        } else |err| {
            std.log.warn("err {}", .{err});
        }
    } else |err| {
        std.log.warn("err {}", .{err});
    }
    const exe_unit_tests = b.addTest(.{
        .root_source_file = b.path("src/main.zig"),
        .target = target,
        .optimize = optimize,
    });

    const run_exe_unit_tests = b.addRunArtifact(exe_unit_tests);
    test_step.dependOn(&run_exe_unit_tests.step);
}

fn concatAndReturnBuffer(allocator: std.mem.Allocator, one: []const u8, two: []const u8) !std.ArrayList(u8) {
    var b = std.ArrayList(u8).init(allocator);
    try b.appendSlice(one);
    try b.appendSlice(two);
    return b;
}